Method and apparatus for casting ingot molds



@EST AvAaLABLE COPY April 20 1926., "1,581,541

Y J. E. PERRY METHOD AND APPARATUS FOR CASTING lINGrOT MOLDS Filed March 27, 1923 2 Shets-She'et 1 2 BY u2 MATTORNEY @d na@ 46 51 AVMLABLE COPY J. E. PERRY METHODv AND APPARATUS-FOR CASTING INGOT MOLDS Filed March 27, 1923 2 Sheets-Sheet 2 tillllll INVENTOR LzzzPerry BY a ATTORNEY -v betweenv the walls of the flask EEST AVAlLABLE COPY Patented Apr. 20, 1926.

UNETED S'iA'lESv LSSLSAE PATENT OFFICE.'

JOHN E. PERRY, OF SHARON, PENNSYLVANIA.

METHOD AND APPARATUS non CASTING INGoT MoLns.

Application filed March 27, 1923. I Serial No. 627,943. I

,and useful Improvements in Methods and Apparatus for Casting lngot Molds, Vof which the following is a specification.

This invention; relates broadly to metallurgy and more especially to a method and an apparatus for casting ingot molds.

Heretofore in the art of casting ingot molds the method of procedure has been substantially as follows:

A flask is set up and the parts claniped securely together. and a thin metal stripping plate temporarily attached to the bottom thereof. The mold pattern, assuming it to be of the vertical type, is set on the ramming floor and the flaskis raised by a crane and dropped over -the mold pattern.` The workmen manipulate these parts largely by a mattei' of judgn'ient, and set the i'iask over the. pattern without any definite rentering of the two members. Mol-d sand is then rammed and the pattern. This frequently springs the temporary stripping from the flask and causes an uneven sand surface on the bottom of the flask. After the ramming is completed the flask with the sand therein is stripped from the pattern by using a crane and the temporary stripping plate released and removed. The "flask is then set upon a rack and the workmen proceed to cnt the bottom, i. c., to cut the sand at the bottom back even with the flask and cut the gate opening, and the moldfis then set on the racks for drying. Even with the most careful manipulation during this operation the sand at the bottom of the flask is often torn or broken away, and itis necessary to patch the broken places. Very often if the flask should be accidentally bumped the greater part of the sand will drop out, making it necessary to re-ram the flask. If the broken places can be patched, the patching is done with newsand, usually of a different temper than -the sand used in the original ramming, and with a'very different degree of compactness as compared with the original ramming. One expedient practiced in trying to overcome this difficulty has been in the use of fresh loam sand for ramming the bottom part of the flash in an effort to provide suiiicient strength to support the old or 'mixed sand'in the upper portion of the fiask after the strippingplate'has been re moved. This fresh loam sand is particularly liable to burn and stick to theca'st-ing, there by making bad castings which either must b'e rejected or which will require excessive labor in chipping and ,finishing'the ingot mold before ,such mold can besold for use. After the flask has been rammed and the bottom cut back it is then blacked and dried..

Since ingot molds'are hollow cast `iron members, it is necessary to provide a large core which forms a matrix part of the cast ingot mold when finished.

setting the core box around the core bar and rannning the sand between the box and the core bar, without special setting or centeri ng of the box and the bar. When the box' is stripped from the bar. the core is smoothed, blacked and dried in 'the core oven. vThe bottom of the core bar usually is'provided with a cast iro-n plate `whichisadapted to set loosely in a recess in the casting plate, but does notproject tol form a part of the matrix side wall. When the 'sandiu the flask and on the core bar is properly. dried the core is set up in the opening in the casting plate. The flask is then picked up by a crane and set over the core bar1 which core bar is then straightened by the workman who relies principally upon his eye to cent1-alize the core'bar in the opening in the flask as nearly asl possible. The ask is then lifted fromv the core' bar by -a crane and is Set down at one side on the casting floor while a workman stops the opening around the bottom of the core bar by ram-l ming sand therein. This operation is very liable to, and often does, disturb the vertical set of the core bar. After this operation is completed the sand at the bottom of the core bar is blacked and dried. The workmen then measure from the core bar and mark on the casting plate the measurements. where two inside corners of the flask should set, measuring from the core already ser. The flask is again picked up by the crane and set over the core and the workmen proceed to manipulate it into position usually with pinch bars. A fountain or pouring box is then placed over the :frate which has an openingparallel to the matrix of the flask and which leads to an opening in the bottom of the sand which was cut in the sandduring the time the flask was on the rack for The core'is u sually formed around thecore bar member by cutting back the bottom. The set-up is. now ready' lfor pouring vand the molten metal passes from the fountain or pouring box through the gate and rises in the space bebetween the matrix and the flask and around the core bar to form the ingot mold.

The difficulty with this practice in the prior art is the excessive amount of labor and crane operation occasioned by the manipulations required and by the breaking away of sand at the bottom of the flask duringthe drying or handling after the temporary stripping plate has been removed due to the fact that there is no permanent support for the sand after lthe temporary stripping plate has been removed. The workmen in cutting back the sand at the bottom of the flask do not always get itcut evenl and -when it is set up it leaves a bad joint into which the molten metal runs causing fins and sometimes runouts which are difficult and expensive to remove. The core bar is liable to be disturbed from the proper vertical position during the manipulations of the set-up and the whole matter of efficiency of the set-up depends. almost l entirely upon the skill of the workmen employed. Even with the most skillful workman it is practically impossible to center the core in the matrix of the flask, thereby producing ingot molds of uneafen wall thickness which is very detrimental to the use and life of the ingot mold. When it is realized that ingot molds are exceedingly large,

' heavy castings, it will be appreciated that the rejection of a mold is no small item.

The present invention completely overcomes the difficulties of the known prior art and provides a novel method and apparatus which not only insures better results, but which eliminates a large number of manipulations heretofore deemed to be necessary, and by providing a chilled, machined joint between the sand mold parts and the casting or bottom plate. This eliminates all fins at the bottom of the ingot mold, thus very materially reducing the cost of nishing the ingot mold.

In the new method the flask which is formed in sections is provided with a permanent metal stripping plate of relatively heavy metal which is securely attached to the bottom of each section of the flask.

This eliminates all springing away of the plate from the bottom of the flask and makes a perfect sand surface at the bottom of the flask. This stripping plate extends inwardly and is eut away to provide an opening which exactly fits the bottom portion of the mold pattern when the several sections of the flask are joined together and when the flask is liftedand dropped over the mold pattern the pattern is accurately centered and held in position by the stripping plate which assures a uniform thickness of sand throughout the flask. The permanent stripping plate supports the sand throughout the operation, consequently when the flask is stripped from the pattern there is no breaking or dropping away 0f sand and it is not necessary to cnt back the sand at the bottom as in the prior art. When the flask is stripped from the pattern the gate is cut, and the flask is blacked and set on the rack for drying. It is understood that the stripping plate vis not necessarily permanently secured to vthe flask but may be detachably secured thereto so that stripping plates may be changed from time to time to permit interchangeability of the flask. However, the stripping plate is permanently attached so far as its function and use is concerned with a particular flask and the use thereof. Furthermore, Where desired a stripping plate may be retained only in position on the flask until the sand is thoroughly dried and then this plate may be removed before setting up operation.

According to the present invention the A core bar is provided with. an accurately machined base or stripping plate which extends outwardly from the core bar to approximately the distance equivalent to the thickness of the sand which is to be packed around the core bar. Since. a stripping plate on the bottom of the core bar extends outwardly a distance equivalent to the-sand that will be packed around the core bar, it follows that the stripping lplate exactly fits the bottom of the core boX and consequently accurately centers'the bottom of the core bar in the core box. A suitable gauge may be then attached to the top of the core bar and to lock it in definite location to the top of the core box so that these parts are maintained in accurate definite relation While workmen ram the san'd between the core bar and the box. After the ramming operation is completed the box may-be stripped from the core and the core blacked and put in an oven to dry. Preferably the casting plate is recessed to receive the projection on the bottom of the core bar to accurately center the core bar on this casting plate during the setting up and casting operation. This construction exposes the core bar stripping plate as a part of the side wall of the matrix,v

which plate may slightly chill the inner bottom corner of the mold being cast around the core bar. This chilling effect is very slight and tends to prevent any fin forming on the bottom of the cast mold. The casting plate, however, may be provided with a recess opening of sufficient depth to receive the stripping plate so that the sand extends the full length of the core so far as the matrix of the mold is concerned.

After the core is set up on the casting plate, the flask with the sand therein is set over the core and the casting plate may be provided with guide holes arranged near the outer edge thereof to receive guide pins which pass through the bottom 'flange of the flask and also theI stripping plate. When these guide pins are in position the flask is accurately and perfectly set on the casting plate and since theV stripping plates on both the core bar and the flask are accurately machined, a very` accurate set up is obtained. Preferably the stripping plate is metal of sufficient thickness -to slight-ly chill the molten metal at the joint between the stripping plate and the casting plate, so that it is not necessary to pack sand or luting material in the joint. This completely eliminates all fins whichv otherwise would tend to be formed when the ingot mold is cast. After the set-up is completed the casting operation proceeds according to theold practice.

The primary object of the present invention is a method and an apparatus which accomplishes complete automatic alignment and centering of the parts during the ramming, both as to Jthe core bar and core box and the flask and the mold pattern, also 'during the setting up and casting operation as to core and flask. This elminates the necessity for skilled4 labor; reduces time; .simplifies crane operation and obviates defects in the finished ingot mold, which defects under the old practice required hand finishing to the mold.

Other and further objects of the present invention Will in part be obvious and will in part be pointed out hereinafter in the specification following by reference to the accompanying drawings throughout which like parts are indicated by like characters. It is recognized that. the present invention may be embodied in constructions other than those disclosed herewith and therefore the disclosure herewith is to be considered as illustra-tive and not in the limiting sense.

Figure 1 is a cross section through a completed set-up of one form of apparatus for carrying out the presentinvention.

Figure 2 illustrates the mold pattern held in position in the flask by means of the stripping plate.

Figure 3 is a plan view of the stripping plate.

Figure 4 is a cross section of the core box and core bar therein, with one half the core box removed.

Figure 5 is a plan view of one form of bottom or casting plate.

Figure 6 is a sectional view taken on line 6-6 of Figure 5.

Figure 7 is a plan view of one form of core bar guide to hold in position during the remaining operation.

The present invention may be carried out by the following apparatus, comprising a.

flask 1 which preferably is `made in sections BEST AVAILABLE COPY and to which is attached stripping plates 2.' These stripping plates preferably are removably attached to the flask 1 by means of T- head key bolts 4 Which pass through open` ings 5 in the sections of the stripping plates and through the lower flange 6 of the flask l1 so that the flask sections and the stripping walls 1() of the flask. A gate stick 1'1 is set in the gate. stick opening 12 and sand is rammed tightly between the gate stick, the

pattern, and the flask Walls. The flask with the sand therein is thenpstripped from the mold pattern and dried.

A core bar la is ina similar manner set up ou a. rannning floor plate 15 in the core box 1(3'. rlhe bottoni 0f this core bar is provided with a machined base 17 having angular sides 18 and a flat stripping plate 19. This stripping plate exactly fits in the bottom of the core box and centers the base of the core bar in the core box. A gage 20 preferably is dropped over the upper end of the core bary within the core box. During this operation the hinged side arms 2l may be lifted whenevera particular side arm interferes with the ramming operation at that point and after the operation is completed beneath the particular arm, the arm is then dropped down in position to secure the core bar while the ramming progresses around other portions of the annular space between the bar and the box. lVhen the ramming operation is completed the core box is carefully removed together with the gage 20, and the stripping plate or base of the core bar sustains the sand side wall that is packed around the core bar. The core bar is then dried in any well knovi manner and the parts are ready for assembly. A

The bottom plate may be formed with a recess as shown in Figures 5 and 6 to comprise a receptacle which receives and supports the machined base 18 of the core bar shown in Figure 7. The flask with the rammed sand therein is then set down over the core bar and is positioned in such manner that the holding down T-bolts 24 may be passed through the flange G of the flask and the stripping plate section thereon and through openings 25 in the bottom plate. This accurately secures the flask in a -definite position on the bottoni plate. It is to be understood that the stripping plate T- bolts 4 are located in the flange 6 of the flask intermediate the positions for the holding down T-bolts 24 as will be observed from a comparison of openings in Figs. 2 and 5. The parts will now be located as illustrated in Figure l with the flask and the core bar definitely positioned so that the matrix 26, which will comprise the finished ingot mold, is formed with definite shaped side walls of predetermined thickness. A suitable fountain 27 is placed in position over the gate and the usual practice in pouring is followed.

From the foregoing description .it will be clear that the present method and apparatus accurately determines the conditions which control the final results and eliminate errors which have heretofore been dependent upon the human element in manufacture of ingot molds, as well as greatly simplifying the manipulation of the parts during ramming and setting up operations.

Having thus described my invention, I

claim l. The method of preparing a sand mold for casting an ingot mold, said method comprising, positively centering a mold pattern within a flask, ramming mold sand between the pattern and the flask, and directly supporting the rammed sand wall when the flask is being stripped from the pattern.

2. The method of preparing a sand mold for casting an ingot mold, said method comprising positively centering a mold pattern within a flask, ramming mold sand between the pattern and the flask, stripping the ask from the pattern, and directly supporting the ramlned sand wall when the flask is being stripped from the pattern.

3. The method of preparing a sand mold for casting ingot molds, which comprises automatically centering a mold pattern within an empty flask on a ran'nning floor, ramming sand between the .pattern and the walls of the flask, and supporting the base of the sand wall independently of the ramming floor.

4. The method of preparing a sand mold for casting ingot molds, which comprises placing a mold pattern within an empty flask on a ramming floor, Yramming sand between the pattern and the walls of the flask to forni a sand mold, and supporting the base of the sand wall independently of' the ramming floor.

5. The method of preparing core bars for casting ingot molds, which method comprises positively and automatically centering a core bar within a core box, ramming sand between the core bar and the core box, and supporting the base portion of the sand independently of the ran'iming floor.

. 6. The method of preparing core bars for casting ingot molds, which method comprises placing a core bar within a core box,

ramming sand between the core bar and the core box, and supporting the base portion gf' the sand independently of the ramming oor.

' 7. The method of preparing core bars for casting ingot molds which method oomprises, positively centering a core bar within a core box, ramming mold sand between the core box and core bar, and directly supporting the sand on the core bar against gravity when the core box is-removed.

' 8. The method of preparing core bars for casting ingot molds, which methodl oomprises positively centering a core bar within a core box by positively securing both ends thereof, ramming mold sand between the core box and core bar, and indirectly supporting at all times the sand on the bottom of the core bar against gravity when the core box is removed.

9. The method of preparing a set up for casting ingot ymolds, which method comprises placing a mold pattern within an empty flask and ramming sand between the flask and the pattern, supporting the flask sand at all times against gravity; placing a core bar within a core box and ramming sand around the core bar, supporting the corebar sand at all times against gravity, positively mounting the said core bar in a definite predetermined position on a bottom plate, and positively mounting' the said mold in the flask in a predetermined position on the said bottom plate whereby the relation between said sanded core bar and said Saud mold in the flask is automatically predetermined.

10. The method of preparing a set up for casting ingot molds, which method coniprises placing a mold patternv within an empty flask and ramming sand between the flask and the pattern, supporting the bottom layer of the flask sand at all times against gravity; placing a core bar within a core box and ramming sand around'the corebar, supporting the bottom portion of the core bar sand at all times against gravity, positively mounting the sanded core bar in a definite predetermined position on a bottom plate, and positively mounting the sand mold in the flask in a predetermined position on the said bottom plate whereby the relation betweensaid sanded core bar and said sand mold in the flask is automatically predetermined.

il. The method of preparing a set-up for casting ingot molds,- which method comprises automatically centering a mold pat-- tern within an empty flask and ramming sand between said pattern and said flask, supporting at all times the lowermost portion of said sand in said flask, automatically centering a core bar within a core box and ramming sand around said core bar, supporting at all times the lowermost portien 0f the sand on the Corebar against gravity, positively securing said core bar in a vertical vposition on a bottom plate, and positively mounting said flask in a predetermined position on said bottom plate.

12. The method of preparing a set-up for ,casting ingot molds, which method comprises' 'oenteringa mold pattern vwithin an empty flask and ramming sand between said pattern and said flask, supporting the lowermost portion of said sand at 'all times, centering a core bar Within a Core box and ramming sand around said core bar, sup porting at all times the lowermost portion of the sand on the core bar against gravity, securing said core bar in la Vertical position on a bottom plate, and mounting said flask in a predetermined position on said bottom plate.

13. In the art of casting ingot molds, or the like, a flask adapted to sustain a sand matrix 'for use in casting ingot molds, in combination with a stripping plate attached to said flask and being` adapted to completely support at all time-s the bottom por- ;tion of rammed sand between the sand matrix wall and the Wall of the flask.

14. In the art of casting ingot molds, or the like, a flask adapted to sustain a sand matrix for use in Casting ingot molds, in combination With a stripping plate provided with an'opening adapted to fit the base of a mold pattern, said plate being attached to said flask and being adapted to completely support at all times the bottom portion of rammed sand between the sand matrix Wall and the Wall of the flask.

15. In the art of casting ingot molds, or the like, a flask adapted to sustain a sand matrix for use in casting ingot molds, in combination with a stripping plate permanently attached to said flask and being adapted to completely support at all times the bottom portion of rammed sand between the sand matrix Wall and the Wall of the flask.

16. In the art of casting ingotA molds, or t-he like, a flask adapted to sustain a sand matrix for use in casting ingot molds, in combination with a stripping plate attached t0 said .flask and being adapted to completely support at all times the bottom portion of rammed sand between the sand matrix wall and the wall of thel flask, said plate being provided with gas vents leading from the sand wall and beneath the flask.

17. In the art of casting ingot molds, or the like, a flask adapted to sustain a sand matrix for use in casting ingot molds, in combination with a stripping plate provided with an opening adapted to fit the base of a mold pattern, said plate being permanently attached to said flask and being adapted to completely support at all times the bottom portion of rammed sand between the sand BEST Avait/aste com matrix Wall'and the wall of the flask and to form a joint With' a suitable bottom plate.

18. In the artof casting ingot molds, or the like, a flask adaptedto sustain a sand matrix for use in casting ingot molds, in combination with a stripping plate'attaohed to said flask and being adapted to complete- 'ly support at all times the bottom portion of rammed sand between the sand matrix wall and the VWall of the flask, and means securing said plate in position on the bottom of said flask to permit said plate and flask to be separated when it is desired to change the plate for one of a different pattern, said plate also being provided with gas vents leading from the said Wall and beneath the flask.

. 19. In the art of casting ingot molds, or the like, a flask adapted to sustain a sand matrix for use in casting ingot molds, in eoinbination'with a stripping plate provided with an opening adapted to fit the base of' a mold pattern, said plate being attached to said flask and being adapted to completely support at all times the bot-tom portion of rammed sand between the sand matrix Wall and the wall of the flask, and means securing said plate in position on the bottom of said flask.

20. In the art of casting ingot molds, or thelike, a-flask adapted to sustain a sand matrix for use in casting ingot molds, in combination with a strippingplate provided with an opening adapted to fit the base of a mold pattern, said plate being attached'to said flask and being adapted to completely support at all times the bottom portion of rammed sand between the sand matrix Wall and the Wall of the flask, and means securing said plate in position on the bottom of said flask, said plate also being provided with gas vents leading from the sand Wall and beneath the flask.

21. An apparatus for casting ingot molds comprising in oon'ibination a bottom plate, a core bar having a base adapted to lit said plate, means for securing said core bar in a definite vertical position on said bottom plate, a flask adapted to carry a sand mold comprising the matrix for casting an ingot mold, and means for securing said flask to said bottom. plate in a definite relation to said core bar.

22. An apparatus .for casting ingot molds comprising in combination a bottom plate. a eore bar having a base adapted to lit said plate, to cause said core bar to stand in a definite vertical position on said bottom plate, a flask adapted to carry a sand mold comprising the matrix for casting an ingot mold, and means for positioning said flask on said bottom plate in a. definite relation t0 said core bar.

23. An apparatus for casting inOot molds or the like, comprising a flask adapt ed to support a sand mold comprising the matrix for casting an ingot mold, a stripping plate beneath said flask and adapted to support the lower portion of said sand, a core bar, a stripping plate at the base of said core bar and adapted to support the bottom portion of sand on said core bar, a bottom plate, devices to definitely position said core bar upright upon said bottom plate, and means to definitely position said flask on said bottom plate in a predetermined relation to said core bar.

2st. An apparatus for casting ingot molds or the like comprising a flask provided with afiange and adapted to support a sand mold comprising the matrix for casting an ingot mold, a stripping plate beneath and attached to said flask and adapted to support the lower portion of said sand, a core bar, a stripping plate attached to the base of said core bar and adapted to support the bottom portion ot' Sand on said core bar, a bottom plate, devices to definitely' position said core bar upright upon said bottom f plate, and means comprising pins extending through said flange on the flask to definitely position said fiask on said bottom plate in a predetermined relation to said core bar.

25. An article of manufacture comprising a core bar, and a Stripping plate in the bottom of said core bar, which stripping plate extends outwardly a distance equivalent to the thickness of the sand wall which said bar is adapted to support, and with the edge of the stripping` plate exposed to comprise a part of the core member adapted to Contact with the molten metal When the core bar is in use.

26. An article of manufacture comprising a core bar adapted to have a sand wall BEST AVAlLABLE COPY formed thereabout, and a stripping plate on the bottom of said core bar adapted to support the lower end of said sand Wall, the outer periphery of said stripping plate forming a continuation of said sand wall for a substantial distance.

27. An article of manufacture comprising a core bar adapted to have a solid Wall formed thereabout, and a stripping plate integral with the bottom of said core .bar and extending outwardly from the core bar a distance equal to the thickness of the sand wall to support the lower end thereof, the outer periphery of said stripping plate forming `a kcontinuation of said sand Wall to chill the lower end of a casting formed thereabout.

28. An article of manufacture comprising a core bar adapted to have a Sand wall formed thereabout, a base plate on they bottoni of said core bar `adapted to position same on a. suit-able base, and a stripping plate extending outwardly from said base plate and said core bar to support the'loyver end of said sand wall. f

29. An article of manufacture comprising a. corebar adapted to have a sand wall formed thereabout, abase plateon thebottom of said core bar adapted to position-same on a suitable base, and an integralfstripping plate extending outwardly from -saidbase plate and said core bar to supportthe lower end of said sand wall with thel outer periphery of the stripping plate being a Ac011- tinuation of the sand Wall to term a metallic zone about the bottom of the core-member to chill the bottom of a castingV formed thereabout.

JOHN E. maar 

